α-[(2,5-Dioxopyrrolidin-1-yl)oxycarbonyl]-4-hydroxybenzeneacetic acid

[[(2,5-dioxopyrrolidin-1-yl)oxy]carbonyl](4-hydroxyphenyl)acetic acid

α-[[(2,5-Dioxo-1-pyrrolidinyl)oxy]carbonyl]-4-hydroxybenzeneacetic acid